Image synthesis is a technique of analyzing a background image to select a suitable position in the background image for combining a foreground image and combining the foreground image onto the background image. For example, a foreground image may be a user's photograph taken for personal use and a background image may be a street view of the location where the photograph was taken. A joint image of the foreground and the background image allows the user to re-experience the atmosphere of the time and place.
More specifically, a service called street view search is currently available on the Internet and background images taken around the world are stored on the servers. By downloading a desired background image and compositing the background image with an image of a person taken by a user, the atmosphere of the time and place can be reproduced with many angles. The function termed “past-experience simulation” allows a user to re-experience the atmosphere of the time and the place through the combined use of user's personal photographs and the street view search service.